cros: stop forcing off display when powerd reports SuspendDone

ash/system/power/tablet_power_button_controller_unittest.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/system/power/tablet_power_button_controller.h"
 
 #include <memory>
 
 #include "ash/ash_switches.h"
 #include "ash/public/cpp/config.h"
@@ skipping 550 matching lines @@
 // Tests that when backlights get forced off due to tablet power button, media
 // sessions should be suspended.
 TEST_F(TabletPowerButtonControllerTest, SuspendMediaSessions) {
   ASSERT_FALSE(shell_delegate_->media_sessions_suspended());
   PressPowerButton();
   ReleasePowerButton();
   ASSERT_TRUE(GetBacklightsForcedOff());
   EXPECT_TRUE(shell_delegate_->media_sessions_suspended());
 }
 
+// Tests that when system is suspended with backlights forced off, and then
+// system resumes due to power button pressed without power button event fired
+// (crbug.com/735291), that we stop forcing off backlights.
+TEST_F(TabletPowerButtonControllerTest, SuspendDoneStopsForcingOff) {
+  PressPowerButton();
+  ReleasePowerButton();
+  power_manager_client_->SendBrightnessChanged(0, false);
+  ASSERT_TRUE(GetBacklightsForcedOff());
+
+  // Simulate an edge case that system resumes because of tablet power button
+  // pressed, but power button event is not delivered.
+  power_manager_client_->SendSuspendDone();
+
+  EXPECT_FALSE(GetBacklightsForcedOff());
+}
+
 }  // namespace test
 }  // namespace ash